While praising "Fox & Friends" yesterday as the best (and highest-rated) morning political show, the president went off on its competitors:

"Morning Psycho (Joe), who helped get me elected in 2016 by having me on (free) all the time, has nosedived, too," he tweeted. "Angry, Dumb and Sick. A really bad show with low ratings - and will only get worse. CNN has been a proven and long term ratings and beyond disaster. In fact, it rewarded Chris Cuomo with a now unsuccessful prime time slot, despite his massive failure in the morning. Only on CNN!"

(Joe Scarborough, noting that his ratings keep rising, jabbed Trump with the banner "Morning Psycho Responds to Faithful Viewer," saying "he just can't quit us." Cuomo's prime-time show, while in third place, has settled in as the highest rated show on his network.)

Trump also unloaded on the "stupid" New York Times columnist Paul Krugman, calling him "obsessed with hatred," and saying the paper "will have to get down on their knees & beg for forgiveness-they are truly the Enemy of the People!"

(Krugman, whatever one thinks of his commentary, is a Nobel Prize winner in economics.)

Maybe this simply reflects how the president revels in staying on offense. He's happiest when attacking those he believes have treated him unfairly, especially in the media.

But he may well be reacting to the renewed impeachment chatter on the airwaves, especially MSNBC, and among Democrats like AOC who don't agree with Nancy Pelosi's decision to avoid such a move. The speaker's argument: the party can hold Trump accountable for "highly unethical and unscrupulous behavior" without wading into the impeachment bog.

Kamala Harris has now joined Elizabeth Warren in the pro-impeachment camp, but most of the other 2020 candidates are not ready to hop on the bandwagon.

What's striking is the unmistakable shift in tone among impeachment advocates in the days since the Mueller report was unveiled.

They know — and acknowledge — that it would dominate the news for many months and blot out any remnants of a Democratic agenda.

They know — and acknowledge — that it would fire up the Trumpian base.

They know — and acknowledge — that the Republican-controlled Senate would not even come close to convicting Trump.

"Obstruction of justice is a crime. If Trump committed that crime, he's a criminal. Are we simply going to allow a criminal to sit in the Oval Office and face no consequence? Are we simply going to let the next presidential election be the point at which Trump is punished or rewarded?

"It is maddening to think that we are at such a pass. But, my mind is made up: I say impeach him."

And here's the rationale: "I say that there is no such thing as a failed impeachment. Impeachment exists separately from removal ...

"So, an impeachment vote in the House has, to this point, been the strongest rebuke America is willing to give a president. I can think of no president who has earned this rebuke more than the current one. And, once a president is impeached, he is forever marked.

"Whether or not this is politically wise, failing to impeach would be a grave abdication. If you want people to believe that the misdeeds enumerated in the Mueller report are serious, you have to act like it. To not even try to impeach Trump is to collaborate in the Trumpian fiction that he has done nothing impeachable."

So impeach or be complicit. This is the emerging "moral duty" argument of liberal adherents, who say it requires putting politics aside. In fact, the founders adopted impeachment as an explicitly political remedy for an unfit leader who had not necessarily committed crimes.

"If House Democrats impeach Trump ... they will be sorely disappointed. They will wake up the day afterward and, after all the drama and wall-to-wall coverage, he'll still be president of the United States, tweeting per usual.

"Impeachment would be a symbolic mark against Trump, but at what cost? Impeachment won't magnify the president's alleged offenses but will make them smaller as the argument devolves into a microscopic examination of his words and actions (and non-actions). It would be the most forlorn impeachment ever."

If impeachment is viewed as a gussied-up censure vote, rather than a constitutional remedy, then the liberals who are pushing it don't care if it's forlorn or not. They just want to do something cathartic, regardless of the real-world consequences.

But the Democrats who fervently want Donald Trump out of office have a better option: Beat him at the ballot box next year.